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Q129537: PRB: APPEND BLANK Fires Field-Level Validation

Article: Q129537
Product(s): Microsoft FoxPro
Version(s): 3.00
Operating System(s): 
Keyword(s): 
Last Modified: 25-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SYMPTOMS
========

Issuing an APPEND BLANK on a table in which fields have validation rules may
cause this error:

  Field <fieldname> violation rule is violated.

CAUSE
=====

The APPEND BLANK command adds blank values to all the fields of a new record,
unless default values are specified. If a blank or default value in a field
violates a validation rule, an message indicating the rule was violated will
occur.

RESOLUTION
==========

Specify default values for fields that have validation rules, or set table
buffering and Multilocks on before issuing an APPEND BLANK command. To enable
buffering, open the table, and type the following commands in the Command
window:

     SET MULTILOCKS ON
     =CURSORSETPROP("Buffering",n)  && n may be any value from 2 - 5.

See the Visual FoxPro Help menu for more information on the CURSORSETPROP()
function.

To achieve buffering through the Visual FoxPro interface, choose Options from the
Tools menu. Then select the Data tab. Under the Locking and Buffering section,
place a chack mark in the Multiple Record Locks check box to set multilocks on.
Set Buffering to any setting except Off.

STATUS
======

This behavior is by design.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

Create a new database or open an existing database (.DBC file). Type the
following commands in the Command window to create a one-field table (MyTable)
and append a blank record:

     SET MULTILOCKS OFF
     CREATE TABLE MyTable (cFld1 C(10) CHECK !EMPTY(cFld1))
     =CURSORSETPROP("buffering",1)
     APPEND BLANK                      && The message appears!
     SET MULTILOCKS ON
     =CURSORSETPROP("buffering",2)
     APPEND BLANK                      && The record is appended, no message!

When executing the APPEND BLANK command, Visual FoxPro attempts to store a blank
value in cFld1. This violates the NOT EMPTY rule specified in the CREATE TABLE
command, so a message indicating the rule violation occurs.

Additional query words: VFoxWin

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : 3.00

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